2.3 Lobatae section
This study included 4 species in Lobatae section which is only found in the New World (Table 2). Average length of equatorial axis and polar axis of pollen (27.72 μm and 30.1 μm) in this section is between Quercus and Protobalanus but closer to the average length in Quercus section than that in Protobalanus section. Pollen shapes tend to be spheroidal. Surface ornamentations of Lobatae pollen include scabrate and scabrate-verrucate, both dense and sparse. Moran’s test shows that there is phylogenetic signal in distance between pores between each taxa (Table 8)
The sizes of Quercus Xalvordiana , Q. macdonaldiiChrysolepis chrysophylla , and Notholithocarpus densiflorusvar. echinoides are between Protobalanus and other 2 sections. In addition, variation of sizes of Lobatae oak pollen is larger than that of Protobalanus even though two sections include the similar number of species. p /D ratios between three sections did not show significant difference.
Table 3 Light microscope measurements in three Quercus sections. size (lengths of equatorial axis and polar axis), shape (P/E ratio), and furrow distance (p/D ratio)